1. Field of the Invention
This invention relates to a cylindrical cutting element for a coal cutting machine with a reamer-conveyor worm or reamer spiral, disposed projecting at a distance from the surface of the cutting element and made of base elements attached at uniform distances. A chisel holder with an exchangeable chisel is connected to each base element. The chisel holder is inserted with its plug-in connector into a socket of the base element and is maintained therein by a pressure screw.
2. Description of Prior Art
A cutting element of this type is taught by German reference DE 92 11 739 U1. It is necessary to prepare a welding template which is positioned and fastened on the surface of the cutting element. The positions of the individual base parts as well as their alignment on the cutting element are marked. The base parts can then be held and welded on in sequence, so that the reamer-conveyor worm or reamer spiral is produced.
This method is very time-consuming, because it is necessary to produce an individual welding template and to apply it very exactly to the cylindrical cutting element. There is often the danger that the template is placed with insufficient accuracy or that the individual base parts are inaccurately placed for being welded together. This leads to an unsatisfactory geometry of the reamer-conveyor worm or reamer spiral and results in a reduction of the quality of the surfaces milled by the coal cutting machine. Furthermore, the service life of the cutting element is greatly reduced by inexpertly applied base parts, because the forces transmitted through the chisel are not guided through the support surfaces provided, so that the chisel holder is more easily torn off.